Magic Tiramisu

Combine the coffee and alcohol: Dissolve the coffee in the boiling water, then add 100ml cold water and the grappa, Tia Maria, Marsala or sherry.

Make the sponge layer: Arrange the sponge fingers in a 20cm square shallow dish (or tin), making a double layer. Spoon the coffee mixture evenly over the biscuits.

Prepare the topping: Beat the sugar and yoghurt into the mascarpone, then spread this over the biscuits, pressing down well once they are all covered. Pile the grated chocolate on top, then spread it out and press down. Chill for 10 minutes in the freezer, if possible.